Description
The Allen-Bradley 1756-IA16I is a 16-channel digital input module designed for the ControlLogix platform. It is specifically engineered to monitor 120V AC field signals in industrial environments. The module features individual channel isolation, which allows each input to operate independently without sharing a common reference. This design is critical for applications where field devices are powered by different sources or where electrical isolation is required to prevent ground loops and improve signal integrity.
Features
- 16 individually isolated input channels for enhanced noise immunity.
- Wide operating voltage range: 79 to 132V AC (47 to 63 Hz).
- Supports producer/consumer communication model for efficient data sharing across the ControlLogix backplane.
- Configurable Requested Packet Interval (RPI) and Change-of-State reporting.
- Input timestamping capability with approximately ±200 microseconds accuracy for event-driven applications.
- Compatible with standard 36-pin Removable Terminal Blocks (RTB).
Applications
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Heavy Manufacturing: Monitoring safety switches, gate interlocks, and proximity sensors.
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Oil, Gas, and Chemical: Interfacing with 120V AC E-stops, valve limit switches, and motor control centers.
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Power Distribution: Reading status feedback from high-voltage circuit breakers and switchgear indicators.
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Water/Wastewater: Controlling pumps and filtration systems with isolated sensor returns.
Technical Specifications
| Parameter |
Specification |
| Input Voltage |
120V AC |
| Operating Voltage Range |
79 to 132V AC (47-63 Hz) |
| Number of Channels |
16 (Isolated) |
| Backplane Current (5V) |
125 mA |
| Backplane Current (24V) |
2 mA |
| Power Dissipation (Max) |
4.9 W at 60 degC |
| Off-State Current (Max) |
2.5 mA |
| On-State Current |
5 mA (min) to 15 mA (max) |
| Operating Temperature |
0 to 60 degC |
Installation Guidelines
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Chassis Mounting: Install only into an approved ControlLogix 1756 chassis.
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ESD Protection: Always wear an approved grounding wrist strap when handling the module to prevent electrostatic discharge damage.
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Power Safety: While the ControlLogix platform supports Removal and Insertion Under Power (RIUP), ensure the area is free of hazardous gases before performing maintenance.
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Wiring: Use a 36-pin Removable Terminal Block (RTB) such as the 1756-TBNH (cage-clamp) or 1756-TBSH (spring-clamp). RTBs are sold separately.
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Environment: Mount the system inside a tool-secured enclosure with a 5VA flame-retardant rating.
Compliance and Certifications
The 1756-IA16I is designed for industrial use and carries certifications including UL, c-UL-us, CE, C-Tick, EAC, and KC. It also holds marine certifications from ABS, BV, DNV, GL, and LR.
FAQs
What is the 1756-IA16I?
The Allen-Bradley 1756-IA16I is a 16-channel, individually isolated AC digital input module belonging to the ControlLogix platform.
Can this module be hot-swapped?
Yes. The ControlLogix chassis platform supports Removal and Insertion Under Power (RIUP).
Which Removable Terminal Block (RTB) should I use?
The module requires a 36-pin RTB. You can use either the cage-clamp style (1756-TBNH) or the spring-clamp style (1756-TBSH). Note: RTBs are sold separately.
Can this module be placed in a remote I/O rack?
Yes, it can be mounted in a local controller chassis or placed in a remote I/O chassis communicating via EtherNet/IP or ControlNet networks.